Golf balls are traditionally made with multiple layers superposed on each other. Each layer is typically included to impart a particular quality to the ball.
The cover, for example, provides an outer scuff protection and provides particular aerodynamic properties to the ball. The aerodynamics of the ball are governed by many factors, but are frequently governed by the size, shape, and arrangement of the dimples on the exterior surface of the cover. The durability and scuff resistance of the ball is governed by additional factors, but is also governed by the material from which the cover is made.
The material or materials used to form the interior of the golf ball typically determine other flight and feel characteristics of the ball. The density of the core, for instance, typically determines the compression of the ball. The compression of the ball affects, for example, the distance a ball flies when struck by a club. For example, a golfer with a slower swing, like that common with a less experienced golfer, may achieve a better distance with a golf ball having a lower compression. The lower the compression number, the more the ball compresses on impact and the softer the core.
Other layers may be present in the ball as well. These layers may be inserted to affect the compression of the ball or to control spin or the like.
When a ball includes multiple superposed layers, a designer often must choose between two potentially undesirable options. A first undesirable option is for the layers to simply be placed adjacent one another without securing the layers to one another. If the layers are positioned in such a manner, the layers will tend to shift with respect to one another, possibly as often as with each stroke. This shifting will tend to create bunching and discontinuities in the ball, which leads to the cracking of the cover and a quick deterioration of the ball. The other undesirable option is for the designer to secure adjacent layers together with adhesive. If adhesive is used, the recyclability of the ball is reduced. The inclusion of adhesive adds so much effort in and energy expense to the recycling process due to the effort in some instances to separate the layers and in other instances to remove the adhesive residue that would tend to cling to one or the other of the adjacent layers. In still other instances, both of these processes would need to take place before any recycling could take place. The time and energy expended in doing one or more of these processes dramatically reduces or eliminates the benefits desired from recycling.
Therefore, it is desirable to develop a cost-effective process for recycling a multi-layer core or inner part of a ball. It is also desirable to develop a ball that may be used in such a process, particularly if the ball includes minimal adhesive.